დაუშვებელია in English:

This is totally unacceptable.

It is highly regrettable that your request was considered to be unacceptable.

Cancelling the meeting at this late stage is completely unacceptable.

When I arrived on Rozprza, I found an unacceptable situation.

The children were told that running along the corridors was unacceptable behaviour.

The team lost the basketball game 32–68 and their coach said the score was unacceptable.

his behaviour was unacceptable

Acceptable and unacceptable are clearly in opposition to each other.